Background and Objective: Today, we face increasing number of caesarean section as an unnecessary medical technology. In fact, performing caesarean section without medical reason has many harmful consequences for mother and her baby. The current study was aimed to determine the effect of planned behavior-based educational intervention on the selection of childbirth method among primipara women who visit health centers of Tehran during 2016-2017.Methods: This was a semi empirical study, with pre-test, post-test design and control group. 120 primiparas who visited health centers were randomly categorized into intervention and control groups. Data was collected by researcher-made questionnaire based on the construct of the theory of planned behavior, and after confirming its validity and reliability, was distributed between the statistical samples. The collected data was analyzed using SPSS16.Results: The descriptive findings showed that intervention and control groups were demographically homogenous. The inferential findings showed that between the average of both groups in all construct, except for the behavioral ones, there was no meaningful difference before the educational intervention (P>0.001) while after that, the difference of average were meaningful (P<0.001).Conclusion: The results indicated that the program has a positive effect on improving the selection of childbirth method among primiparas as they are more tended to natural childbirth than caesarean section. Therefore, the construct of the theory of planned behavior can be used to encourage such women to choose natural childbirth instead of caesarean section.